Polymer of acetylene derivatives, which possess a one-dimensional main chain having a .pi.-electronic conjugate system and are characterized by the conductivity and nonlinear optical effect, are widely studied as electronic functional material.
A method of manufacturing polyacetylene, by polymerizing acetylene gas with a Ziegler-Natta catalyst, proposed by Shirakawa et al., is well known (Synthetic Metals, vol. 1, p. 175, 1979/1980, Switzerland).
Polyacetylene derivatives used at the present are, however, unstable against heat, pressure or ultraviolet rays, in an atmosphere containing oxygen. Stabilization studies are being conducted, but effective methods for stabilizing polyacetylene derivatives polymer have not proved satisfactory.